the first technology of its kind... mom and dad, i have great news. is now providing answers families need. siemens. answers. >> neil: you ever watch these guys who go through wreckage and sort of reassemble to try to find out what led -- i remember covering pan am flight 103 disaster and how they took pieces of metal and ultimately brought that whole thing back to moammar gadhafi and libya. remember that? just pieces of wreckage. as the investigation continues in boston, they're doing just that. and they're moving pretty fast. we turn right now to former chicago superintendent and former f.b.i. bomb technician, jody wise. what are they doing? what do they look for with each and every piece of twisted metal they goat their hands on? >> they're look for clues and it's amazing how much remains from a bomb when it actually detonates, the fusing system, although it will be fragmented, much of the container, there can be residue, there can be fragmentation left over. but they're look for clues. you can have a circuit board. there might be a partial fingerp